A review on recent development in the spinel ferrites-based materials for efficient solar fuel (hydrogen) generation via photocatalytic water-splitting

The world's energy crisis and environmental problems could be addressed via solar fuel (hydrogen) generation. Thus, the development of non-toxic, inexpensive and high-efficiency photocatalysts is crucial. Spinel ferrite with general formula MFe2O4 (where M=Mg2+, Co2+, Ni2+, Zn2+, e.t.c.) has gained enormous interest in the field of solar energy conversion and storage especially solar fuel (hydrogen) generation via photocatalytic water splitting. Spinel ferrites are considered as ideal materials for solar fuel (hydrogen) generation due to its promising magnetic recovery, suitable band gap energy, low toxicity, strong thermal stability, affordability, simple preparation method, and magnetic retrieval ability. However, the solar-to-hydrogen (STH) conversion efficiency of spinel ferrite materials is still low due to high rate of photogenerated electron-hole pair recombination, resulting in poor photocatalytic performance. Herein, preparation approach for spinel ferrites is reviewed in details. Importantly, the solar H2 production improvements achieved in the study of the spinel ferrites material as main photocatalyst not a co-catalyst were exclusively reviewed and discussed. Thus, this review would likely motivate researchers to broaden the applications for spinel ferrites-based materials in solar fuel (hydrogen) generation in an economical and eco-friendly approach.